The Object-Oriented Thought Process

The Object-Oriented

Thought Process

Fourth Edition

Matt Weisfeld

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The Object-Oriented Thought Process, Fourth Edition

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ISBN-13: 978-0-321-86127-6

ISBN-10: 0-321-86127-2

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First Printing March 2013

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Contents at a Glance

Introduction

1 Introduction to Object-Oriented Concepts

2 How to Think in Terms of Objects

3 Advanced Object-Oriented Concepts

4 The Anatomy of a Class

5 Class Design Guidelines

6 Designing with Objects

7 Mastering Inheritance and Composition

8 Frameworks and Reuse: Designing with Interfaces and

Abstract Classes

9 Building Objects and Object-Oriented Design

10 Creating Object Models

11 Objects and Portable Data: XML and JSON

12 Persistent Objects: Serialization, Marshaling, and

Relational Databases

13 Objects in Web Services, Mobile Apps, and Hybrids

14 Objects and Client/Server Applications

15 Design Patterns

Index

Table of Contents

Introduction

This Book’s Scope

What’s New in the Fourth Edition

The Intended Audience

The Book’s Approach

This Book’s Conventions

Source Code Used in This Book

1 Introduction to Object-Oriented Concepts

The Fundamental Concepts

Objects and Legacy Systems

Procedural Versus OO Programming

Moving from Procedural to Object-Oriented Development

Procedural Programming

OO Programming

What Exactly Is an Object?

Object Data

Object Behaviors

What Exactly Is a Class?

Creating Objects

Attributes

Methods

Messages

Using Class Diagrams as a Visual Tool

Encapsulation and Data Hiding

Interfaces

Implementations

A Real-World Example of the

Interface/Implementation Paradigm

A Model of the Interface/Implementation Paradigm

Inheritance

Superclasses and Subclasses

Abstraction

Is-a Relationships

Polymorphism

Composition

Abstraction

Has-a Relationships

Conclusion

Example Code Used in This Chapter

The TestPerson Example: C# .NET

The TestShape Example: C# .NET

2 How to Think in Terms of Objects

Knowing the Difference Between the Interface and the

Implementation

The Interface

The Implementation

An Interface/Implementation Example

Using Abstract Thinking When Designing Interfaces

Providing the Absolute Minimal User Interface Possible

Determining the Users

Object Behavior

Environmental Constraints

Identifying the Public Interfaces

Identifying the Implementation

Conclusion

References

3 Advanced Object-Oriented Concepts

Constructors

When Is a Constructor Called?

What’s Inside a Constructor?

The Default Constructor

Using Multiple Constructors

The Design of Constructors

Error Handling

Ignoring the Problem

Checking for Problems and Aborting the Application

Checking for Problems and Attempting to Recover

Throwing an Exception

The Importance of Scope

Local Attributes

Object Attributes

Class Attributes

Operator Overloading

Multiple Inheritance

Object Operations

Conclusion

References

Example Code Used in This Chapter

The TestNumber Example: C# .NET

4 The Anatomy of a Class

The Name of the Class

Comments

Attributes

Constructors

Accessors

Public Interface Methods

Private Implementation Methods

Conclusion

References

Example Code Used in This Chapter

The TestCab Example: C# .NET

5 Class Design Guidelines

Modeling Real-World Systems

Identifying the Public Interfaces

The Minimum Public Interface

Hiding the Implementation

Designing Robust Constructors (and Perhaps Destructors)

Designing Error Handling into a Class